Stair-lift.



N0. 685,|I6. Patented Oct. 22, |90I.

\ J. M. DDGE.

STAIR LIFT.

(Application led Mar. 30, 1901.) `(No Model.) 2 Sheets-Sheet I.

No. 6a5,||6. Patented not. 22,|9o\.

J. M. DODGE. v

STAIR LIFT. (Application med Mar. so. 1961.) i (No Model.) 2Sheets-Sheet 2.

Ybelt illustrated in Fig. 1.

UNITED STATES PATENT OFFICE.

JAMES M. DODGE, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE STAIRLIFT COMPANY, OF CAMDEN, NEW JERSEY, A CORPORATION OF NEW JERSEY.

sTAlR-LIFT;

sPEcIFIcATIoN ruiming partof Letters Patent No. 685,1 16, grated october22, 1901. Application tiled March 30, '1.901. Serial No. 53,'l63l. (Nomodel.)

The object of my invention is to provide lmeans for taking the drivingstrain from the iiexed portion of the stair-lift in order to reduce thefriction and strain upon the belt.

My invention is an improvement upon the device illustrated and claimedinl an application for patent iled byme on the 7th day of January, 1901,Serial No. 42,411. In the above-mentioned application a supplementalcoupling-belt is used, engaging the carryingbelt during a portion of itstravel only, whereas the belt illustrated and claimed in the presentapplication is practically a part of the carrying-belt and is capable ofbeing lengthened or shortened' to agree with the carryingbelt, so thatthe drivingstrain is not taken by the carrying-belt, but by thesupplemental belt or chain.

In the accompanying drawings, Figure 1 is a longitudinal sectional viewthrough sufficient of a stair-lift to illustrate my invention, thecarrying-belt being shown in dotted lines. Fig. 2 is a section on theline 2 2, Fig. 1. Fig. 3 is a perspective View showing a detail of theFigs. 4 and 5 are views showing the means for lengthening and shorteningaI section of the belt in its two positions. Figs. 6, 7, and 8 arediagram views showing the means of shifting the mechanism shown in Fig.3 from the position shown in Fig. 5 to that shown in Fig. 4 at the lowerD at the end and around a drivingwheel D', at the lower end in thepresent instance, although power may be applied to D2 D3 are shaped at dd' to accommodate the enlarged portions of the chains or belts I. Themain portion 't' of the chainpis of the ordinary link-and-pin type inthe present instance, and each section is coupled at one end by theenlarged link z' to an axle B and connected at the other end to anarched link i2, which is in turn pivoted to a lever I', hung on the axleB. (Clearly illustrated in Figs. 3, 4, and 5.) On the end of the lever Iis a wheel e, and at one side of the lever is a second wheel e, somewhatless in diameter than the wheel e in the present instance.

When the lever I is in the position shown in Figs. 3 and 4, a section ofthe belt is contracted, and when the lever is forced over to theposition shown in Fig. 5 a section of the belt is lengthened. On thereturn run the sections of the belt are lengthened and on the exedportion of the carrying-run the sections are contracted. This isaccomplished by means of the rails and cam-surfaces shown in Fig. 1.Inthe irst place, when the belt passes around the lower wheel D3 thewheel e on the lever I travels upon the cam-rail f, as shown .in Fig. 6,causing the lever to move in the direction of the arrow, andconsequently will contract the section of belt bethe point f2 of therail F, as shown in Fig. 1,

when the lever will be thrown completely over. link 'i2 to the lever I',will then be on a dead- The pivot-point 3, which couples the center andthe lever will not have a tendency to throw over; but in order to guardagainst accident the lever is held down by the body of the rail F, whichextends up to a point near the upper end ot the stairway, where it isdiscontinued, and the lever is then under the control of a rail F',which is curved in the present instance. This rail F acts upon the wheele', gradually lifting the lever I and throwing the pivot i3 ott the dead-center. IVhen the lever reaches the upper end ot the rail F', thesection of the belt will be lengthened prior to passing around thehead-wheel D2, as clearly shown in Fig. l. Thus it will be seen thatsections of the chains or belts will be lengthened at certain points oftheir travel and be shortened at other points, and the levers are socontrolled that the sections will be shortened when the carrying-belt isflexed to form treads and risers and when the carrying-belt passesaround the carryingwheels, and on the return run the sections of thechain or belt will be lengthened. Thus the driving strain is taken bythe coupling belt or chain when the step sections are flexed, andconsequently there is a saving in power and in wear and teal' of theapparatus.

While I have shown a chain, a rope may be used in place ot the chain, ifdesired.

I claim as my inventionl. The combination in a stair-lift, of'acarrying-belt, means for fiexing said belt on the carrying-run of thestair-lift, a coupling-belt attached at intervals to the carrying-belt,and means for lengthening and shortening said coupling-belt,substantially as described.

2. The combination in a stair-lift, of a carrying-belt, means forflexing said belt on the carrying-run of the stair-lift, a coupling-beltattached at intervals to the carrying-belt, and means for lengtheningand shortening sections of said coupling-belt between the points ofattachment, substantially as described.

3. The combination in a stair-lift, of a carrying-belt, means forflexing said belt on the carrying-run to form treads and risers, acoupling-belt attached at intervals to the carrying-belt, the sectionsof said coupling-belt between the points of attachment being capable ofbeing lengthened or contracted, and rails for automatically contractingor lengthening the said sections, substantially as described.

4. The combination in a stair-lift, ofa carrying-belt, means for flexingthe said belt to form treads and risers, axles at the points of fiexure,a coupling-belt attached to the carrying-belt at the alternate axlesforming a series of sections, and means for contracting each section asthe treads and risers are formed, whereby the driving strain will betaken by the coupling-belt, substantially as described.

5. The combination in a stair-lift, of a carryin g-belt,wheels aroundwhich the belt passes, means for flexing the said belt to form treadsand risers on the carrying-run of the stairway, a coupling-belt attachedat intervals to the'carrying-belt, the section of the belt between thecoupling being capable of being lengthened or shortened, with means forautomatically shortening the coupling-belt when the carrying-belt isflexed to form treads and risers, and means for lengthening thecoupling-belt when the carrying-belt reaches the upper end of thestairway, substantially as described.

6. The combination of an endless carryingbelt, means for fiexing thesaid belt to form treads and risers, axles at the points of ilexure, acoupling-chain at each side of the carrying-belt and attached toalternate axles, and means for lengthening or shortening the sections ofchain between the alternate axles, substantially as described.

7. The combination in a stair-lift, of a flexible endless carrying-belt,means for fiexing the belt to form treads and risers, axles at the pointof fiexure, levers pivoted to each alternate axle, a chain extendingfrom an axle t0 the level', and means for operating the lever so as totake up the slack in the chain when the carrying-belt is flexed,substantially as described.

8. The combination in a stair-lift, of a carrying-belt, axles on saidbelt, means for flexing the belt to form treads and risers,couplingchains at each side of the carrying-belt, said coupling-chainsbeing attached to alternate axles, one of the links of said chain beingin the form of a lever and rails for controlling the position of thesaid lever, whereby it is thrown to one side or the other of the axle towhich itis pivoted so as to lengthen or shorten the section of belt ofwhich it forms a part, substantially as described.

9. The combination in a stair-lift, of a flexible carrying-belt, meansfor fiexing the belt to form treads and risers, axles at the nose ofeach tread, a coupling-belt made in sections, each section beingattached to an axle forming a continuous coupling-belt, a lever foriningpart of each section, and rails for operating the lever to lengthen orshorten the belt, substantially as described.

10. The combination in a stair-lift, of an endless carrying-belt, meansfor fiexing the belt to form treads and risers, coupling-belts at eachside of the carrying-belt and connected to the carrying-belt atintervals, each section ot' belt between the points of attachmentconsisting of a chain and a lever to which one end of the chain isattached, said lever having two wheels, one outof line with the other,and fixed rails also arranged out of line so as to actuate the levers,substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

. JAMES M. DODGE.

NVitnesses:

WILL. A. BARR, Jos. H. KLEIN.

IIO

